There are many situations where it is necessary or desirable to detachably secure two items or workpieces together. For example, housing sections used to enclose or contain a product must be fastened in some manner so as to be secure when the product is used, but preferably the housing sections are detachable so that they can be removed to allow access to the product (e.g., for repair purposes).
Various types of products require the type of enclosure or containment described. Such products include, for example, gears, electronics, linkages, tubing or wiring which must be clamped or secured in place, and other various mechanisms. The workpieces may be housings for electrical components, mounting or clamping devices, or locating components of a mechanical gear train or linkage.
Various types of fastening devices can be used to detachably secure items such as housing sections to each other or to a product to be enclosed. For example, various types of threaded fasteners or other mechanical fasteners have been used for this purpose. However, this requires that additional components be used, thereby increasing the cost of the enclosure.
The use of a conventional cantilever beam with a hook on its outer end is also known as a means for securing two workpieces together. In such case, the outer end of the cantilever beam is inserted into an opening in the second workpiece. However, when a tensile load is exerted on the arm it can pull free of the second workpiece relatively easily. This is because the force exerted on the hook portion of a cantilever beam is not centrally applied to the beam. As a result, when a tensile load is exerted on the arm a moment is created which forces the beam to deflect. As the beam deflects, the angle of the hook portion changes such that a component of the force pushes the end of the beam back even further. Eventually the hook portion slips free and the workpieces become detached.
Other conventional types of fastening systems include hook and loop fasteners (such as VELCRO brand fasteners), over-center latches, and press fit fasteners (e.g., where a post is pushed into an opening with great force to frictionally engage the walls of the opening). Each of these systems has limitations, however. Hook and loop fasteners have structural limitations. Latches can be complex and also costly. Press fit fasteners may lose their effectiveness after being detached one or more times.
There has not heretofore been provided a locking system of the type described herein for detachably securing two workpieces together.